MRI contrast agents are often metallic--and have known toxicity issues with some shown to remain in the body longer-term as deposits in the brain. The benefits of using MRI imaging for patients have been assumed to outweigh these potential risks. However, new NIH-backed research could eventually render these concerns moot. An international research team has created a method for imaging brain tumors that uses a common form of sugar D-glucose, which is also known as dextrose. The method capitalizes on the fact that tumors consume more sugar than normal tissues. "This is the first non-metallic, biodegradable, natural MRI contrast agent tested in humans," explained Guoying Liu, director of the National Institute of Biomedical Imaging and Bioengineering Program (NIBIB) in Magnetic Resonance Imaging and Spectroscopy. "Developing these natural contrast agents is critical for patients who require repeated imaging; additionally it will increase patient acceptance and comfort with imaging procedures." NIBIB is part of the U.S. National Institutes of Health. In a pilot study consisting of four normal volunteers and three brain tumor patients, the new MRI approach gave comparable results to metallic enhancing agent gadolinium. Research was conducted at the Johns Hopkins University School of Medicine, Kennedy Krieger Institute in Baltimore and at Lund University in Lund, Sweden. "It is a significant step to be able to obtain clear MRI images of the brain using a biocompatible substance that is metabolized naturally by the body relatively quickly," said Peter van Zijl, Chief of Neuroscience at the Division of MR Research at Johns Hopkins and senior author. "The dose of D-glucose is similar to that used for diabetes testing and is much cheaper than the metallic agents." More